OK open to ideas here with this one :-
we have a mcb style mains board (crabtree from memory) which has an RCD device built in. Normally when when for an example a bulb goes the trip for that lighting circuit goes bit of a pain but we can live with it. However yesterday and today has been a nightmare with the main breaker tripping on average every two hours! No individual circuit goes and throwing the break brings everything back to normal (apart from having to reset the times on the cooker microwave stero etc!).
At a loss for any ideas. Nothing has changed regarding load no new devices etc and its happened day and night so its not something we are manually turning on or off.
any ideas where to start ?